The present invention relates to a photography apparatus for television picture and, more particularly, to a photography apparatus for taking photographs of television picture images for originals of printing.
A need has recently arisen for printing a desired television picture it in great numbers. For this purpose, in general, the image on the screen of a color television receiver is photographed by a still camera. The obtained color photograph is placed in an electronic color scanner for producing four color separation plates for color printing: a Y (yellow) plate, an M (magenta) plate, a C (cyan) plate and a BK (black) plate. Since the color television picture of the NTSC system is a moving picture of 30 frames per second, the shutter speed must be slower than 1/30 second for obtaining a photograph with a camera. The color temperature of the phosphorescent material painted on the screen of the cathode ray tube (CRT) of a television receiver is about 9,000.degree. K. On the other hand, a color film is manufactured for general use in daylight, and its color temperature is in the range of 5,000.degree.-6,000.degree. K. Thus, a color temperature converting filter must be used for taking a photograph. However, since three kinds of phosphorescent material red, green and blue are painted on the CRT, the light-energy distribution of the phosphorescent material and the film-speed distribution of the film emulsion do not coincide, resulting in a color photograph which is unacceptable as an original. Further, since these phosphorescent materials of three different colors are painted in dotted form, does appear in the photograph and it is unacceptable in this respect, as well. That is, a photograph is enlarged beyond a certain degree, the dots become notable and resolving power is adversely affected. A television picture is constituted by 525 scanning lines regardless of the size of the picture and thus does not give a picture of good resolving power. Thus, the influence of the dots is fairly large.
Since the shutter speed must be considerably slow, the image may be blurred in photographing a fast-moving object, for example in photographing the images of a sport broadcast. Thus, it has been proposed not to directly photograph the television picture but to record the television signals by a video tape recorder (VTR) first, and then to photograph one frame picture reproduced by the VTR in the still frame mode. However, it is difficult to determine which frame to photograph among the frames recorded on one video tape. It is particularly difficult to determine which frame to print when the client and the printer are different and the client supplies a video tape with recorded television signals to the printer for printing. The client takes in advance a photograph of a predetermined frame to be printed with an instant camera and supplies the printer with this photograph and the tape counter value of the VTR read on an order mode. Then the printer determines which one is this predetermined frame by referring to this photograph and the counter value. However, several frames are included in one count of the counter. Accordingly, it is almost impossible for the printer to correctly determine the frame the client specified. It has also been proposed to record a time code signal representative of the hour, minute, second, and frame in an audio track of a video tape for specifying the frame. This time code signal can be generated by an already available SMPTE time code signal generator or a VITC signal generator. However, this type of signal generator is expensive, thus limiting the use of it. Further, the printer side must also have a detector for signals, resulting in an increase in cost both for the client and the printer.